High power semiconductor laser array with single-mode emission

The semiconductor laser array with single-mode emission is presented in this paper.The 6-μm-wide ridge waveguides(RWGs)are fabricated to select the lateral mode.Thus the fundamental mode of laser array can be obtained by the RWGs.And the maximum output power of single-mode emission can reach 36 W at an injection current of 43 A,after that,a kink will appear.The slow axis(SA)far-field divergence angle of the unit is 13.65.The beam quality factor M;of the units determined by the second-order moment(SOM)method,is 1.2.This single-mode emission laser array can be used for laser processing.

A 795 nm gain coupled distributed feedback semiconductor laser based on tilted waveguides

The 795 nm distributed feedback lasers have great application in pumping the Rb D1 transition.In this paper,in order to realize specific 795 nm lasing,we designed tilted ridge distributed feedback lasers based on purely gain coupled effect induced by periodic current injection windows through changing the angle of the tilted ridge.The fabricated devices were cleaved into 2 mm-cavity-length,including 5 tilted angles.The peak output powers of all devices were above 30 mW.Single longitudinal mode lasing was realized in all tilted Fabry-Perot cavities using periodic current injection windows,with side mode suppression ratio over 30 dB.The total wavelength range covered 8.656 nm at 20℃.It was disclosed theoretically and experimentally that the output powers,threshold currents,and central wavelengths of the tilted ridge purely gain coupled DFB lasers were relevant to the tilted angles.The results will be instructive for future design of DFB laser arrays with different central wavelengths.

Chronic wound biofilms: diagnosis and therapeutic strategies

Objective:To review the diagnosis of chronic wound biofilms and discuss current treatment approaches.Data sources:Articles included in this review were obtained from the following databases:Wanfang,China National Knowledge Infrastructure,PubMed,and the Web of Science.We focused on research published before August 2019 with keywords including chronic wound,biofilm,bacterial biofilms,and chronic wound infection.Study selection:Relevant articles were selected by carefully reading the titles and abstracts.Further,different diagnosis and clinical treatment methods for chronic wound biofilm were compared and summarized from the selected published articles.Results:Recent guidelines on medical biofilms stated that approaches such as the use of scanning electron microscopy and confocal laser scanning microscopy are the most reliable types of diagnostic techniques.Further,therapeutic strategies include debridement,negative pressure wound therapy,ultrasound,antibiotic,silver-containing dressing,hyperbaric oxygen therapy,and others.Conclusion:This review provides the identification and management of biofilms,and it can be used as a tool by clinicians for a better understanding of biofilms and translating research to develop best clinical practices.